#!/usr/bin/env python3

"""

Analyze TypeForm parsing efficiency from mypy build stats.

Usage:

python3 analyze_typeform_stats.py '<mypy_output_with_stats>'

python3 -m mypy --dump-build-stats file.py 2>&1 | python3 analyze_typeform_stats.py

Example output:

TypeForm Expression Parsing Statistics:

==================================================

Total calls to SA.try_parse_as_type_expression: 14,555

Quick rejections (no full parse): 14,255

Full parses attempted: 300

- Successful: 248

- Failed: 52

Efficiency Metrics:

- Quick rejection rate: 97.9%

- Full parse rate: 2.1%

- Full parse success rate: 82.7%

- Overall success rate: 1.7%

Performance Implications:

- Expensive failed full parses: 52 (0.4% of all calls)

See also:

- mypy/semanal.py: SemanticAnalyzer.try_parse_as_type_expression()

- mypy/semanal.py: DEBUG_TYPE_EXPRESSION_FULL_PARSE_FAILURES

"""

import re

import sys

def analyze_stats(output: str) -> None:

"""Parse mypy stats output and calculate TypeForm parsing efficiency."""

# Extract the three counters

total_match = re.search(r"type_expression_parse_count:\s*(\d+)", output)

success_match = re.search(r"type_expression_full_parse_success_count:\s*(\d+)", output)

failure_match = re.search(r"type_expression_full_parse_failure_count:\s*(\d+)", output)

if not (total_match and success_match and failure_match):

print("Error: Could not find all required counters in output")

return

total = int(total_match.group(1))

successes = int(success_match.group(1))

failures = int(failure_match.group(1))

full_parses = successes + failures

print("TypeForm Expression Parsing Statistics:")

print("=" * 50)

print(f"Total calls to SA.try_parse_as_type_expression: {total:,}")

print(f"Quick rejections (no full parse): {total - full_parses:,}")

print(f"Full parses attempted: {full_parses:,}")

print(f" - Successful: {successes:,}")

print(f" - Failed: {failures:,}")

if total > 0:

print()

print("Efficiency Metrics:")

print(f" - Quick rejection rate: {((total - full_parses) / total * 100):.1f}%")

print(f" - Full parse rate: {(full_parses / total * 100):.1f}%")

print(f" - Full parse success rate: {(successes / full_parses * 100):.1f}%")

print(f" - Overall success rate: {(successes / total * 100):.1f}%")

print()

print("Performance Implications:")

print(

f" - Expensive failed full parses: {failures:,} ({(failures / total * 100):.1f}% of all calls)"

)

if __name__ == "__main__":

if len(sys.argv) == 1:

# Read from stdin

output = sys.stdin.read()

elif len(sys.argv) == 2:

# Read from command line argument

output = sys.argv[1]

else:

print("Usage: python3 analyze_typeform_stats.py [mypy_output_with_stats]")

print("Examples:")

print(

" python3 -m mypy --dump-build-stats file.py 2>&1 | python3 analyze_typeform_stats.py"

)

print(" python3 analyze_typeform_stats.py 'output_string'")

sys.exit(1)

analyze_stats(output)